Development of a Volumetric Mix Design Approach for Fine Aggregate Matrix (FAM) and Validation with Micro-CT Method

Fine aggregate matrix (FAM) is the primary phase of asphalt concrete (AC) in which important deformation-damage phenomena occur. Many studies have used laboratory testing on FAM to characterize mechanical behavior of asphalt mixtures and have also actively exploited FAM for microstructure modeling of AC mixture and predicting the fracture behavior of asphalt pavements. However, despite the wide agreement in the literature to the significance of matrix phase on overall performance of AC, only limited studies have attempted developing methods of FAM mixture design. This study aims to develop a protocol for volumetric design of FAM based on given AC mixture design parameters. To this end, the outputs of volumetric AC mixture design were used as inputs for calculation of FAM volumetric properties. A series of volumetric equations were derived, and procedures recommended in commonly accepted specifications (e.g., AASHTO, Asphalt Institute) were used to achieve the volumetric FAM mixture design. Additional relations were also considered to allow the use of the proposed mix design protocol for AC mixtures containing reclaimed asphalt pavement (RAP) materials. To further validate the effectiveness and accuracy of the proposed FAM mixture design, FAM specimens were extracted from gyratory compacted samples with varying air void contents. The air void content of extracted FAM specimens was directly measured using an advanced micro-CT scanning technology and compared with the input values. A strong statistical correlation between mix design air voids and micro-CT air voids showed the efficacy as a potential specification-type FAM mixture design method.

• Supplemental Notes:
  • This paper was sponsored by TRB committee AFK50 Standing Committee on Structural Requirements of Asphalt Mixtures.
• Corporate Authors:

  Transportation Research Board

  ,    
• Authors:
  • Amelian, Soroosh
  • Kim, Yong-Rak
  • Osmari, Patr�cia Hennig
  • Aragão, Francisco Thiago Sacramento
  • Braz, Delson
  • 0000-0002-5319-1627
  • Nogueira, Liebert Parreiras
• Conference:
  • Transportation Research Board 98th Annual Meeting
  • Location: Washington DC, United States
  • Date: 2019-1-13 to 2019-1-17
• Date: 2019

Language

• English

Media Info

• Media Type: Digital/other
• Features: References;
• Pagination: 4p

Subject/Index Terms

• TRT Terms: Asphalt concrete; Asphalt mixtures; Fine aggregates; Mix design; Volumetric analysis
• Subject Areas: Design; Highways; Materials; Pavements;

Filing Info

• Accession Number: 01697368
• Record Type: Publication
• Report/Paper Numbers: 19-01178
• Files: TRIS, TRB, ATRI
• Created Date: Mar 1 2019 3:50PM